Radiosignaling apparatus



W. H. NOTT'AGE.

RADIOSIGNALING APPARATUS.

APPLICATION FILED MAR. 3o, 192|.

l 94322854, Patented Oct. 17, 1922,

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entre@ srarns PATENT @FFHQEO 'WILLIAM HOCKLEY NOTTAGE, OF CHELMSFORD, ENGLAND, ASSIGNOR TO RADIO CORPORATION F AMERICA, A CORPORATION OIE DELAWARE.

RADIOSIGNALING PARATUS.

Application led March 30, 1921. Serial No. 456,882.

To @ZZ whom it may concern Be it known that l, W'ILLrnM HOCKLEPY NofrrAGn, a British subject, and a resident of Chelmsford, England, have invented certain new and useful Improvements in Radiosignaling Apparatus, of which the following is a specification accompanied by drawings.

This invention relates to a system of telephony including both land lines and wireless, and its object is to provide an improved system whereby signals received by wireless may be transmitted over land lines and whereby a wireless transmitter may be Operated by signals transmitted over land lines. According to my invention l provide a 1l"Vheatstone bridge each of two adjacent arms of which is formed of one winding of a transformer, such, for instance, as those used in land line telephony for connecting the receiver to the line. T0 two opposite junctions of the bridge I connect the wireless receiver and to the other two junctions ll connect the wirelessl transmitter, and l conneet the land line to the other winding of the transformer of one arm.

With this arrangement signals coming in to the wireless receiver will not affect the wireless transmitter but will a'ect the land line s0 that they can be heard over that land line. Signals transmitted over the land line will not a'ect the wireless receiver' but will aii'ect the wireless transmitter by which they will be transmitted, because the latter is reresponsive to audible frequencies and the former is only a'ected by radio frequencies from the antenna. I

rJlhe second inductive arm of the bridge is preferably formed of one winding of a transformer exactly similar to that connect- 40 ing the land line already mentioned to the bridge.

It may be necessary to balance the land line by an artificial line in this second transformer, and by providing a microphone and telephone in this line an engineer or operator at the wireless station is enabled to supervise the working. Thus he .can listen in to signals received from the wlreless receiver or land line and can also operate the wireless transmitter through the bridge.

In the accompanying diagram A, B, C, D is a bridge, two arms, A and B, including the secondary windings A and B of two similar transformers, the windings preferably being o-f high inductance.

R and R are resistances included in arms A and B for purposes 0f balancing., In the other arms C and D are two impedances, such as condensers C" and D', one or both being variable; they may conveniently be air condensers of the kind used in wireless telegraph receivers.

To the primary winding A of the transformer in arm A, which prima winding should be of the same order of induc-tance and resistance as the transformers usually associated with land telephone lines, is connected a land telephone line E to a telephone exchange or subscriber.

To the primary winding B of the transformer in arm is connected an artificial telephone line F which may be adjustable and of magnitude suitable to balance the effect of the land line E. To thisartiicial line may be connected an ordinary land telephone subscribers set G or a microphone and telephone of any suitable pattern.

rThe junction H of arms A and B and the junction J of arms C and D are connected by lea-ds, which may be screened in metal casing, to the receiver of a wireless telephone set with the addition of any magnitiers required to bring the strength of received sigv nals to a value sufficient to be heard at the subscribers instrument in the line E.

rlhe junctions K of arms A and C, and L of arms B and D, are joined by leads, which may be screened by metal casing, to that circuit of the wireless telephone transmitter usually associated with the microphone, with the addition of any magnifiers required to bring the intensity of speech received from. the land line to a value suitable for actuating the wireless telephone transmitter.

Resistances M N and condenser Q may be provided to join one diagonal, say K L, of the bridge, and a point. between M and N may be brought to earth potential or some suitable potential with reference to the wireless telephone set.

rThe bridge is balanced by adjusting the arms A, B, C and D so that signals from the wireless telephone receiver do not affect the wireless transmitter. rl`his adjustment may be found by connecting a telephone to the leads K and L and adjusting the arms until no signals are heard.

When speech is impressed on the transmitter from the land line, the receiver will not be affected even if speech frequencies do get into it as it is only affected by radio frequencies from the antenna circuit.

Having described` my invention what I claim is zl. In radio signaling apparatus, a Wheatstone bridge having transformer windings in two adjacent arms, a telephone line connected to the other winding of one of the transformers, a wireless telephone receiver connected to two opposite junctions between the arms of the bridge and a wireless telephone transmitter connected to the other two opposite junctions.

2. In radio signaling apparatus, a Wheatstone bridge having transformer windings in two adjacent arms, a telephone line connected to the other winding of one of' the transformers, a wireless telephone receiver having one terminal connected to the junction of the adjacent arms containing-the transformer windings and the other terminal connected to the opposite junction of the bridge and a wireless transmitter connected to the other two opposite junctions of the bridge.

3. In radio signaling apparatus a Wheatstone bridge having transformer windings in two adjacent arms, a telephone line connected to the other winding of one of the transformers, a balancing line connected to the other winding of the other transformer, a wireless telephone receiver connected to two opposite junctions between the arms of the bridge and a wireless telephone transmitter connected to the other two opposite junctions.

4. In radio signaling apparatus, a n heatstone bridge having transformer windings in two adjacent arms, a telephone line connected to the other winding of one of the transformers, a balancing line connected to the other winding of the other transformer, a wireless telephone receiver having one terminal connected to the junction of the adjacent arms containing the transformer less telephone transmitter connected to `bhe other two opposite junctions.

6. In radio signaling apparatus, a lVheatstone bridge having transformer windings in two adjacent arms, and condensers in the other two adjacent arms, a telephone line connected to the other winding of one of the transformers, a wireless telephone receiver connected to two opposite junctions between the arms of the bridge and a wireless telephone transmitter connected to the other two opposite junctions.

7. In radio signaling apparatus, a Wheatstone bridge having transformer windings in two adjacent arms, a telephone line connected to the other winding of one of the transformers, a wireless telephone receiver connected to two opposite junctions between the arms of the bridge, a wireless telephone transmitter connected to the other two opposite junctions, and impedances connected across two opposite junctions of the bridge, and means for grounding an intermediate point of such impedances.

8. In radio signaling apparatus, a Iheatstone bridge having transformer windings in two adjacent arms, a telephone line connected to the other winding of the transformers, a balancing line connected to the other winding of the other transformer, 'a wireless telephone receiver connected to two opposite junctions between the arms of the bridge, a wireless telephone transmitter connected to the other two opposite junctions and means in said balancing line for controlling said receiver and transmitter.

WILLIAM I'IOCKLEY NOTTAGE. 

